Fuel control device

ABSTRACT

A control device having a housing provided with a valve seat and a movable valve member carried by the housing for opening and closing the valve seat. A thermostatically operated device is operatively associated with the valve member for moving the valve member relative to the valve seat. A spring is carried by the housing and is operatively associated with the valve member to tend to move the valve member to close the valve seat, the spring being so constructed and arranged that the spring causes the valve member to substantially always tilt against the same part of the valve seat when the valve member is being moved to open or close the valve seat.

United States Patent 1191 11] 3,827,630 Demi Aug. 6, 1974 FUEL CONTROL DEVICE Prima Examiner-William E. Wa ner P ry y [75] Inventor Roy C Dem! Greensburg a Attorney, Agent, or Firm-CandoryCandor & Tassone [73] Assignee: Robertshaw Controls Company,

Richmond, Va. [57] ABSTRACT 2 Filed; Ju|y 1 1973 A control device having a housing provided with a valve seat and a movable valve member carried by the [21] Appl' 380,212 housing for opening and closing the valve seat. A thermostatically operated device is operatively associated 52 US. Cl. 236/99, 251/321 with the valve therhher for moving the valve member 51 1m. 01. G05d 23/12, Fl6k 1/00 relative to the valve Seat A Spring is carried y the 58 Field of Search .1 236/15 A, 99, 1 E; housing and is eperetively associated with the valve 7 25 32 X member to tend to move the valve member to close the valve seat, the spring being so constructed and ar- 5 References Cited ranged that the spring causes the valve member to UNITED STATES PATENTS substantially always tilt against the same part of the 2 303 on 11/1942 w b t l 236/15 A X valve seat when the valve member is being moved to e er e a. 2,857,131 10/1958 Cole 251/333 x open or close the valve Seat 3,379,406 4/1968 Greer 251/333 X 6 Claims, 6 Drawing Figures PATENTEU B 6 974 SHEET 1 0F 3 FUEL CONTROL DEVICE This invention relates to an improved fuel control device.

It is well known to provide. a fuel control system for a fuel burning apparatus, such as a cooking apparatus or the like, wherein a control device is provided for interconnecting the source of fuel with the burner means for the apparatus, the control device having thermostatically operated valve means for controlling the flow of fuel to the main burner so that the same will tend to maintain an output temperature effect thereof corresponding to the temperature setting of the control device.

Such fuel control system is fully-disclosed in the US. Pats. to Wantz, et al, Nos. 3,132,803 and 3,167,250,

Each control device of such fuel control systems when having its thermostatically operated valve member moved away from the main valve seat, has its valve member uncover a heater pilot valve seat so that fuel can flow to the heater pilot and cause a safety device in the fuel control system downstream from the fuel control device to open and permit the fuel to be passed to the main burner means as long as the heater pilot flame exists at the pilot burner means.

It has been found according to the teachings of this invention that if the valve member of the thermostatically operated valve means of the fuel control device is permitted to randomly tilt relative to the main valve seat as the same initially cracks open, the accuracy of the fuel control device for tending to maintain the output temperature. effect of the burner means being controlled therby at the temperature setting of the control device is diminished because sometimes it will require the thermostatically operated device to move the valve member a greater distance before the same affects the operation of the main burner means that at other times whereby the burner may actually be producing an output temperature effect below or above the desired temperature setting of the fuel control device. Accordingly, initial calibration of the fuel control device will not insure the accuracy desired.

Therefore, it is a feature of this invention to provide such a fuel control device wherein the valve member substantially always tilts against the same part of the valve seat therefor when the valve member is being moved to open or close the valve seat.

In particular, one embodiment of this invention pro vides a control device having a housing provided with a valve seat and a movable valve member carried by the housing for opening and closing the valve seat. Thermostatic means is operatively associated with the valve member for moving the valve member relative to the valve seat. Spring means is carried by the housing and is operatively associated with the valve member to tend to move the valve member to close the valve seat, the spring means being so constructed and arranged that the spring means causes the valve member to substantially always tilt against the same part of the valve seat when the valve member is being moved to open or close the valve seat.

Accordingly, it is an object of this invention to provide an improved control device having one or more of the novel features set forth above or hereinafter shown or described.

Other objects, uses and advantages of this invention, are apparent from a reading of this description which 2 I proceeds with reference to the accompanying drawings forming a part thereof and wherein:

FIG. 1 is a schematic view, partially in cross section, illustrating a fuel control system utilizing the fuel control device of this invention.

FIG. 2 is a view similar to FIG. 1 and illustrates only the fuel control device of this invention with the same being in an on condition thereof.

FIG. 3 is a fragmentary view similar to FIG. 2 and illustrates the thermostatically operated valve means of the fuel control device of this invention in one of its fully opened positions.

FIG. 4 is an end view of the fuel control device of FIG. 2.

FIG. 5 is a view similar to FIG. 3 and illustrates another embodiment of the fuel control device of this invention.

FIG. 6 is a fragmentary cross-sectional view taken on a line 66 of FIG. 5.

While the various features of this invention are hereinafter described and illustrated as being particularly adapted to provide a fuel control device for the burner means of a cooking apparatus, it is to be understood that the various features of this invention can be utilized singly or in any combination thereof to provide a control device for other apparatus if desired.

Therefore, this invention is not to be limited to only the embodiments illustrated in the drawings, because the drawings are merely utilized to illustrate one of the wide variety of the uses of this invention.

Referring now to FIG. 1, a fuel control system is generally indicated by the reference numeral 20 and comprises a fuel source manifold 21 being interconnected by passage defining means 22 to a main burner'23 disposed in an oven chamber 24 of a cooking apparatus that is indicated by dash lines and generally indicated by the reference numeral 25, the passage defining means 22 having a pair of control devices disposed therein in series relation and respectively being generally indicated by the reference numerals 26 and 27.

The first fuel control device 26 comprises a housing means 28 having an inlet 29 adapted to be disposed in fluid communication with the fuel supply manifold 21 and an outlet 30 adapted to be interconnected to a conduit means 31 that forms part of the passage defining means 22 and leads to an inlet 32 of a housing means 33 of the second fuel control device 27.

The first fuel control device 26 has a main on-off valve means that is generally indicated by the reference numeral 34 in FIG. 1 and is adapted to be directly opened and closed by a selector means 35 of the first fuel control device 26 in a manner hereinafter described. The valve means 34 when moved to an open position will supply fuel from the manifold 21 to a valve seat 36 of the housing 28 that is opened and closed by thermostatically operated valve means that is generally indicated by the reference numeral 37.

The thermostatically operated valve means 37, when opening the valve seat 36, permits the fuel to flow from the opened on-off main valve means 34 out through the outlet 30 and thus to the inlet 32 of the second fuel control device 27. The opening of the thermostatic valve means 37 also permits fuel to flow through a sec ond inner valve seat 38 of the fuel control device 26 that leads by a passage means 39 in the housing means 28 to an outlet 40 that is adapted to be coupled by a conduit means 41 to a pilot burner means of the main 3 burner 23, the pilot burner means being generally indicated by the reference numeral 42 and comprising a dual-rate pilot burner means. I

In particular, the pilot burner means 42 is adapted to be continuously fed a flow of fuel at a small rate from the manifold 21 through a passage means 43 of the control device 26 that bypasses the main on-off valve means 34 thereof and leads to the outlet 40 through an adjusting key 44 so that the small amount of fuel that is continuously fed to the pilot means 42 can continuously burn at the pilot burner means 42 to provide a small standby flame 45 even when the selector means 35 is in an of position and the cooking apparatus 25 is not being utilized.

However, when the thermostatically operated valve means 37 opens in a manner hereinafter described, additional fuel is adapted to flow to the outlet 40 of the control device 26 through the opened inner valve seat 38 and interconnecting passage 39 so that the additional fuel flowing to the pilot burner means 42 will create a large heater flame 46 at the pilot burner means 42 that is adapted to be detected by a flame sensor or bulb 47 carried by the pilot burner means 42 and being interconnected to an expandible and contractible member 48 in the housing 33 of the control device 27 by a conduit means or capillary tube 49.

The expandable and contractible element 48 of the control device 27 is interconnected by suitable lever and spring means 50 to a poppet valve member 51 that is normally seated against a valve seat 52 of the housing 33 and thereby blocking the inlet 32 of the housing 33 from an outlet 53 thereof so as to prevent fuel from flowing through the passage defining means 22 to the main burner 23 as the outlet 53 is in fluid communication with the main burner 23.

However, the element 48 expands when the detector 47 is sensing the large heater flame 46 at the pilot burner means 42 and the expansion of the power element 48 causes the lever and spring arrangement 50 to move and hold the poppet valve member 51 from its closed position to a fully open position whereby fuel from the inlet 32 in the control device 27 is now permitted to flow to the outlet 53 thereof and, thus, to the main burner 23 to be ignited by the pilot burner means 42. Thus, as long as the thermostatically operated valve means 37 of the first fuel control device 26 is in an open condition, not only is fuel supplied from the manifold 21 to the second control device 27, but also fuel is supplied to the pilot burner means 42 through the opened valve seat 38 to continuously produce the large heater flame 46 so that the valve member 51 of the fuel control device 27 will remain in an open condition and pass the fuel on to the main burner 23.

However, the thermostatically operated valve means 37 of the fuel control device 26 has an expandable and contractible power element 54 that controls the opening and closing movements thereof, the power element having its interior interconnected by a conduit means 55 to a temperature sensing bulb 56 disposed in the oven chamber 24 and thereby sensing the output temperature effect of the main burner 23.

Thus, when the temperature in the oven chamber 24 exceeds the temperature setting of the selector means 35 of the fuel control device 26, the thermostatic valve means 37 is closed by the expanded power element 54 to not only block the main flow of fuel from the manifold 21 into the conduit 31, but also to block the flow of fuel into the passage 39 of the fuel control device 26 so that the heater flame 46 will no longer be created at the pilot burner means 42. Since the heater flame 46 no longer appears at the pilot burner means 42, the power element 48 of the control device 27 collapses and through the lever and spring arrangement 50 causes the valve member 51 to close against the valve seat 52.

However, due to a thermal lag created by the delay in the time that it takes the power element 48 of the control device 27 to collapse and cause closing of the valve member 51 from the time the heater flame 46 ceases to exist because the thermostatically operated valve means 37 has closed, there is a liklihood that the fuel remaining in the conduit 31 does not have a sufficient pressure to pass out of the burner means 23 and be burned externally thereof so that a flashback situation could exist when the valve means 37 is closed and the control device 27 has its valve member 51 remaining in its open condition due to the thermal lag in the time it takes the power element 48 to collapse.

Accordingly, a bypass passage or orifice 57 is provided through a valve disc 58 of the thermostatically operated valve means 37 to supply sufficient fuel to the outlet 30 to support combustion at the main burner means 23 whenever the valve disc 58 is fully seated against the valve seat 36 and the fuel control device 27 remains open because of the thermal lag in the closing thereof so that the adverse flashback situation will not exist.

Thus, it can be seen that the fuel control device 26 when set in a on position thereof not only opens the main on-off valve means 34 thereof, but also sets the desired output temperature effect of the main burner means 23 so that the main burner means 23 can be cycled on and off in the manner previously described to tend to maintain the output temperature effect in the oven chamber 24 at the output temperature setting of the selector 35 of the control device 26.

Since the details and theory of operation of the control device 27 and dual rate pilot burner 42 is fully set forth in the US. Pat. to Branson, et al, No. 3,367,572 7,572 and the US. Pat. to Riehl, No. 3,405,999, no detailed explanation of the parts and operation of the fuel control device 27 and the dual rate pilot burner means 42 is deemed necessary as any desired information thereon can be obtained from a reading of the aforementioned patents to Branson, et al., and Riehl.

However, the details and operation of the fuel control device 26 of this invention will now be described.

The main on-off" valve means 34 of the control device 26 comprises a poppet valve member 60 that is substantially cup-shaped and has an outer peripheral flange 61 at the open end thereof covered by an annular resilient member 62 adapted to fully seat on an annular valve seat 63 formed in the housing means 28 and surrounding a plurality of openings 64 that lead from a chamber 65 formed in the housing means 28 to a stepped cylindrical chamber 66 formed in the housing means 28, the chamber 65 being interconnected to the inlet 29 while the chamber 66 leads to the annular valve seat 36.

The poppet valve member 60 has a stem 67 passing through a guide opening 68 in the housing 28 in such a manner that a rounded end 69 of the stem 67 is disposed within the chamber 66 and within the path of movement of a cam surface 70 formed on a cylindrical part 71 of a shaft means that is generally indicated by the reference numeral 72 and forming a part of the selector means of the fuel control device 26.

A compression spring 73 is disposed in the chamber and has one end 74 bearing against the housing means 28 and the other end 75 thereof bearing against the poppet valve'member 60 to tend to hold the poppet valve member 60 in its closed position against the valve seat 63.

It can also be seen that the fuel pressure being fed from the source 21 into the chamber 65 of the housing means 28 also acts against the valve member 60 in a manner to hold the valve member 60 in its closed position against the valve seat 63.

Thus, when the selector means 35 is in its off position, the fuel pressure from the source 21, as well as the compression spring 73, act to hold the valve member 60 in its closed position against the valve seat 63 so that even though the usual pressure of the fuel in the manifold 21 should increase through a malfunction in a pressure regulator or the like upstream from the manifold 21, the valve member 60 will not be blown off the valve seat 63 but will be further urged against the valve seat 63 so as to prevent such fuel'from entering into the control system 20 and creating an adverse situation as previously described. e

The shaft means 72 has the shaft part 71 thereof interconnected to a suitable control knob 76 of the selector means 35 and has a shoulder 77 thereof normally urged toward and against the inside surface 78 of a casing member 79 secured to the housing means 28 in alignment with the cylindrical bore or chamber 66 whereby the shaft part 71 closes the left hand side of the chamber 66. If desired, suitable sealing means 80 can be provided on the shaft part 71 to fluid seal the left hand part of the chamber 66 as illustrated in FIG. 1. The shoulder 77 of the shaft part 71 is urged against the surface 78 of the casing 79 by a compression spring 81 disposed within the right hand part of the chamber 66 and having one end 82 bearing against the shaft part 71 and the other end 83 thereof bearing against the housing means 28.

The shaft part 71 has a' stepped bore 84 passing therethrough with the bore 84 having its left hand part 85 internally threaded to receive a threaded adjusting member 86 that carries a member 87 provided with a pair of slots 88 in the right hand end thereof and which respectively receive opposed outwardly directed tangs on the left hand end of a shaft part 90 that has a conical outward extending abutment 91 thereon. The shaft part 90 is adapted to have its right hand end in FIG. 1 extend through an opening 92 in the valve disc 58 of the thermostatically operated valve means 37 with the outwardly directed conical abutment 91 being larger than the opening 92 in the valve disc 58 to carry the valve disc 58 therewith in a manner hereinafter described.

The right hand end of the shaft part 90 is interrupted by a threaded bore 93 which receives a threaded end 94 of a stem member 95 that is carried on a cup-shaped movable wall 96 of the power element 54 which has another cup-shaped wall 97 fixed to a pin means 98 to be carried thereby.

The pin means 98 has a threaded portion 99 adapted to pass through an opening 100 in an end plate 101 of the housing means 28 while a disc like part 102 of the pin 98 is adapted to abut against the inside surface 103 of the plate 101 in the manner illustrated in FIG. 1. With the plate 102 of the pin 98 abutting against the end plate 101, a lock nut 104 can be'threaded on the threaded part 99 of the pin 98 to hold the power element 54 in the position illustrated in FIG. 1, the pin 98 fluidly interconnecting the capillary tube 55 to the spacing between the two cup-shaped members or walls 96 and 97 that have the outer peripheries of the open ends thereof sealed together in a conventional manner.

While the valve disc 58 is loosely disposed on the shaft part 90, the same is either urged toward or against the valve seat 36 or against the conical abutment 91 of the shaft part 90 by a compression spring 105.

In particular, a flexible washer-like member 106 is telescoped onto the shaft member 90 and is disposed against the right side of the disc 58 in FIG. 1. Thereafter, a spring retainer 107 is telescoped onto the shaft part 90 against the washer-like member 106.

A spring retainer 108 is disposed on an enlarged knurled part 109 of the shaft 95 so as to fix the same from rotation thereon, the spring retainer 108 being angled relative to the longitudinal and rotational axis of the shaft means 72 so as to cause the compression spring disposed between the spring retainers 107 and 108 to cause tilting of the valve member 58 during its initial opening movement from the valve seat 36 at the same angle relative thereto each time the valve disc 58 initially opens the valve seat 36 as will be apparent hereinafter as well as each time the valve disc 58 closes the valve seat 36.

Rotation of the shaft means 72 by the knob 76 to the off position illustrated in FIG. 1 causes the shaft part 71 and part 87 interconnected thereto to rotate in unison and thereby rotate the shaft part 90 and cause the same to rotate relative to the threaded end 94 of the pin 95 and thereby axially move to the left relative thereto by unthreading on the end 94 whereby the abutment 91 on the part 90 moves to the left in FIG. 1 a sufficient distance that even though the power element 54 is in its completely collapsed condition, the spring 105 will maintain the valve disc 58 fully seated against the valve seat 36 so as to close not only the valve seat 36, but also close the small valve seat 38 that is disposed inboard of the main valve seat 36 in the manner illustrated in FIG. 1.

However, when the shaft means 72 is rotated by the knob 76 to an on" position thereof, such rotation of the shaft part 71 not only causes the cam means 70 thereof to operate against the rounded end 69 of the poppet valve member 60 to move the same to a fully open condition thereof as illustrated in FIG. 2, but also such rotation of the shaft part 71 causes the member 90 to thread onto the member 94 and be moved to the right in FIG. 1 to abut and move the valve member 58 therewith so that the valve seat 36 will be fully opened as long as the temperature in the oven chamber 24 is not at the temperature setting of the selector means 35.

However, when the power element 54 expands as the temperature in the oven chamber 24 increases, the power element 54 will expand in such a manner that the same will move the valve disc 58 fully against the valve seat 36 when the output temperature effect inthe oven chamber 24 is substantially at or slightly above the set temperature setting of the selector means 35.

From the above, it can be seen that the control device 26 can be formed in a relatively simple manner to provide a positively closed main on-off" poppet valve member and a thermostatically controlled valve means 37 to be utilized in the fuel control system in a manner now to be described.

When the operator desires to utilize the cooking apparatus 25, the knob 76 of the selector means 35 is moved from the off position thereof to the desired temperature setting position thereof. As the shaft means 72 is being rotated by the knob 76, the cam surface 70 of the shaft part 71 acts against the stem 67 of the poppet valve member 60 to move the same to an open position as illustrated in FIG. 2 and hold the same in such open position regardless of where the selector means 35 is subsequently set in any of its oven on" positions.

As previously stated, such rotation of the shaft means 72 causes the member 90 to be more threaded on the threaded end 94 of the pin 95 to a certain position so that the valve disc 58 is held away from the valve seat 36 by the abutment means 91 in opposition to force of the spring 105 and thereby permits fuel to flow from the fuel source manifold 21 through the open poppet valve arrangement 34 and open thermostatically operated valve means 37 to the outlet 30 and, thus, to the safety valve control device 27. Fuel also flows through the opened valve seat 38 to the pilot burner means 42 to create the heater flame 46. When the heater flame 46 is created, the same is detected by the detector 47 and the poppet valve member 51 of the control device 27 is moved to its open position whereby fuel is now adapted to flow to the main burner 23 and be ignited by the pilot burner means 42. The thus operating burner means 23 begins to heat up the oven chamber 24 to the temperature selected by the selector means 35.

When the temperature in the oven chamber 24 reaches the temperature setting of the selector means 35 or is slightly above the same, the power element 54 has expanded in such a manner that the same has caused the valve disc 58 to fully seat against the valve seat 36 and thereby close off the flow of fuel not only to the outlet 30, but also to the valve seat 38 that leads to the pilot burner means 42. In this manner, the heater flame 46 ceases to exist and the control device 27 will subsequently close thereby terminating any flow of fuel to the main burner means 23. As previously stated, during the delay in time from the time the valve disc 58 is fully seated against the valve seat 36, and the valve member 51 of the control device 27 has fully seated against the valve seat 52, the opening 57 through the valve disc 58 supplies sufficient fuel to the main burner means 23 to support combustion at the main burner means 23 so that no adverse flashback situation can exist.

The valve disc 58 remains seated against the valve seat 36 until the output temperature effect in the oven cavity 24 falls below the selected temperature setting thereof whereby the power element 54 is collapsing in such a manner that the same is pulling the shaft part 90 to the right in FIGS. 1 and 2 in such a manner that the conical abutment 91 thereof engages against the valve disc 58 to pull the same to the right therewith. However, because the compression spring 105 has one side held at an angle by the angled spring retainer 108 whereby the spring 105 has its most compressed portion disposed 180 from the valve seat 38, the valve member 58 initially opens relative to the valve seat 36 with a tilting action as illustrated in FIG. 2 so that each time the valve disc 58 is opened relative to the valve seat 36, the same will open with the same angle of tilt so that the flow of fuel that is adapted to pass into the thus open valve seat 38 to cause the heater flame 46 will always occur when the valve disc 58 has been initially cracked open relative to the valve seat 36 at exactly the same position in its opening movement so that proper calibration of the control device 26 can be maintained.

For example, should the valve member 58 be permitted to tilt at any random angle relative to the valve seat 38 during the initial opening of the valve member 58 relative to the valve seat 36, it will require the collapsing of the power element 54 to be at a greater degree of collapse thereof, if the valve member 58 should tilt 180 from the tilt angle illustrated in FIG. 2, before the valve member 58 will permit sufficient fuel to flow into the valve seat 38 to produce the heater flame 46 than when the valve member 58 is permitted to tilt 180 from the valve seat in the manner illustrated in FIG. 2.

Thus, for each temperature setting of the selector means 35, a deviation in the maintained temperature in the oven 24 would take place if the valve member 58 were not caused to open with a tilt relative to the valve seat 36 at exactly the same angle each time the same is cycled by the power element 54 to an open position thereof.

Likewise in the closing of the valve member 58 against the valve seat 36, if the valve member did not initially engage the same part of the valve seat and then angle close at the angle relative to the valve seat 38 each time the valve member 58 was closed by the power element 54, sometimes the heater pilot flame 46 would terminate at a higher temperature than at other times so that the temperature differential being maintained in the oven 24 by the cycling burner means 24 would not be constant for each temperature setting of the control device 26.

Accordingly, while the spring retainer 108 is illustrated as providing the greatest compression to the spring at a position from the valve seat 38, it is to be understood that the spring retainer 108 could be utilized to provide for the disc 58 to tilt 90 relative to the valve seat 38 or even at the valve seat 38 if desired, the important feature being that the tilt of the valve member 58 in its opening and closing movement relative to the valve seat 36 and, thus, relative to the valve seat 38 always be the same for that particular control device 26 so that the particular control device can be properly calibrated in-a manner now to be described.

In the embodiment of the control device 26, it can be seen that by adjusting the threaded relation of the adjusting member 86 in the shaft part 71, the position of the abutment means 91 relative to the power element 54 when the bulb 56 is sensing a certain temperature can be set so that the thermostatically operated valve means 37 will operate to produce the desired output temperature effect in the oven 24 that is selected by the selector means 35 by having the valve disc 58 open when the bulb 56 is sensing a temperature just below the selected temperature of the selector means 35 of the control device 26.

9 Of course, the valve .disc- 58 will continue to move away from the valve seat 36 to the position illustrated in FIG. 3 should the output temperature effect in the oven 24 not increase to the setting of the knob 76 so that an increased flow of fuel will be providedto the burner means 23 through the thermostatically operated valve means 37.

Thus, the valve disc 58 can thermostatically control the flow of fuel from a minimum amount thereof that will support combustion at the burner means 23 to a full flow of fuel thereof as illustrated in FIG. 3.

The control device 26 is so constructed and arranged that when the selector means 35 is set for a broiling operation, themember the member has been threaded on the threaded part 94 of the pin 95 such a distance that the power element 54 will not expand sufficiently to cause the valve disc 58 to fully seat against the valve seat 36 during the broiling operation so that a continuous flame broiling operating can be provided by the burner means 23.

When it is desired to turn off the control system 20, the operator rotates the control knob 76 to the off position of the selector means 35 whereby the flat portion of the cam surface 70 of the shaft part 71 is now adjacent the end 69 of the poppet valve member 60 so that the same can be fully seated against the valve seat 63 not only by the force of the compression spring 73, but also by the force of the fuel pressure in the inlet 29 of the control device 26. Also, such rotation of the shaft part 71 to the off position causes the member 90 to be unthreaded from the threaded end 94 of the pin 95 a distance sufficient that the abutment means 91 thereof will not cause the valve disc 58 to open from the valve seat 36 even though the power element 54 would be in a fully collapsed condition thereof by the bulb 56 sensing very low temperatures, such as room temperature.

While the control device 26 previously described has the adjusting member 86 located in front of the control device 26 adjacent the control knob 76 for adjusting the position of the abutment means 91 relative to the valve member 58 for calibration purposes so that the thermostatic power element 54 will open the valve member 58 when the bulb 56 is sensing approximately the same temperature for which the control knob 76 has been set, the calibration could be accomplished at the rear of the control device 26 if the shaft part 95 could be rotated relative to the spring retainer 108.

Accordingly, another such control device of this invention is generally indicated by the reference numeral 26A in FIGS. and 6,and parts thereof similar to the fuel control device 26 previously described are indicated by like reference numerals followed by the reference letter A.

As illustrated in FIG. 5, the spring retainer 108A is loosely disposed on the pin 95A so as to permit the pin 95A to be rotated relative thereto when the powerelement 54A is rotated relative to the housing means 28A by having the lock nut 104A removed and merely rotating the power element 54A to cause the end 94A to thread in or out of the pin part 90A whereby the part 90A will be moved back and forth and have the abutment means 91A adjusted relative to the movable wall 96A of the power element 54A for the calibration purposes previously described.

In order to permit such rotational movement of the power element 54A and its interconnected pin 95A relative to the spring retainer 108A so that the spring retainer 108A will still cause the valve member 58A to always tilt against the same part of the valve seat 36A that is located l from the valve seat 38Afor the heater pilot, the spring retainer 108A is provided with an L-shaped leg 200 extending therefrom and which is received in a groove 201 formed in the housing 28A in the manner illustrated in FIGS. 5 and 6 so that the L- shaped leg 200 prevents spring retainer 108A from rotating in unison with the rotation of the power element 54A during a calibration procedure.

Thus, it can be seen that when it is desired to adjust the position of the abutment means 91A of the control device 26A relative to the movable wall 96A of the power element 54A so that the abutment means 91A will open the valve member 58A from the valve seat 36A when the thermostatically operated valve means 37A is sensing the set temperature of the control device 26A, the lock nut 104A is loosened and/or removed and by rotating the part 99A at the rear thereof that projects to the right end plate 101A, the rotation of the pin 95A causes the shaft A to axially move relative thereto to the desired position for the abutment means 91A. Such rotation of the pin A is relative to the spring retainer 108A which is held in the proper position from rotation by the L-shaped leg 200 thereof being caught in the groove or recess 201 in the housing means 28A. Thereafter, the lock nut 104A is tightened on the threaded part 99A so as to positively hold the plate 102A against the inside surface 103A of the end plate 101A.

In this manner, even though an adjustment has been made of the thermostatic valve means 37A, the valve member 58A will still substantially alwaystilt against the same part of the valve seat 36A every time the valve member 58A is initially cracked open by the abutment means 91A moving to the right in FIG. 5 because of the collapsing power element 54A as previously described.

Accordingly, it can be seen that this invention provides an improved control device.

While the form of this invention now preferred has been disclosed and described as required by the patent statute, it is to be understood that other forms can be utilized and still come within the scope of the appended claims.

What is claimed is:

l. A control device having a housing provided with a valve seat, a movable valve member carried by said housing for opening and closing said valve seat, means operatively associated with said valve member for moving said valve member relative to said valve seat, and spring means carried by said housing and being operatively associated with said valve member to tend to move said valve member to close said valve seat, said spring means being so constructed and arranged that said spring means causes said valve member to substantially always tilt against the same part of said valve seat when said valve member is being moved to open and close said valve seat, said spring means comprising a coiled compression spring, said spring means including means for normally causing said coiled compression spring to be more compressed on one side thereof that corresponds with said part of said valve seat where said valve member tilts against the same.

2. A control device as set in claim in claim 1 wherein said means for causing said spring to be more coming means being carried by said movable wall means.

5. A control device as set forth in claim 4 wherein said spring retaining means is fixed from moving relative to said movable wall means of said element.

6. A control device as set forth in claim 4 wherein said movable wall means is rotatable relative to said spring retaining means while causing the same to move in unison therewith in an axial direction toward and away from said valve seat. 

1. A control device having a housing provided with a valve seat, a movable valve member carried by said housing for opening and closing said valve seat, means operatively associated with said valve member for moving said valve member relative to said valve seat, and spring means carried by said housing and being operatively associated with said valve member to tend to move said valve member to close said valve seat, said spring means being so constructed and arranged that said spring means causes said valve member to substantially always tilt against the same part of said valve seat when said valve member is being moved to open and close said valve seat, said spring means comprising a coiled compression spring, said spring means including means for normally causing said coiled compression spring to be more compressed on one side thereof that corresponds with said part of said valve seat where said valve member tilts against the same.
 2. A control device as set in claim in claim 1 wherein said means for causing said spring to be more compressed on one side thereof comprises spring retaining means.
 3. A control device as set forth in claim 2 wherein said spring retaining means engages against one end of said coiled compression spring and is angled relative to the longitudinal axis of said spring to cause the same to be more compressed on said one side thereof.
 4. A control device as set forth inclaim 3 wherein said means for moving said valve member relative to said valve seat includes an expandible and contractible element having a movable wall means, saiD spring retaining means being carried by said movable wall means.
 5. A control device as set forth in claim 4 wherein said spring retaining means is fixed from moving relative to said movable wall means of said element.
 6. A control device as set forth in claim 4 wherein said movable wall means is rotatable relative to said spring retaining means while causing the same to move in unison therewith in an axial direction toward and away from said valve seat. 